White paper on crime 2011 Part4/Chapter5/Section3/1
The medical care and treatment system for insane persons, etc. covers  persons who were not prosecuted although deemed to have committed the designated act (homicide, arson, robbery, rape, forcible indecency (including attempt of these offenses), and injury) and they were considered insane or of diminished capacity at the time, and  persons found not guilty for the designated act in a final judgment on the grounds of having been insane at the time or given a mitigated sentence on the grounds of having been of diminished capacity (excluding those sentenced to imprisonment with or without work without suspension of execution of the sentence and who have a specific term to serve). A hearing is held in principle for any such person upon application by public prosecutors. A collegiate court body of a district court that consists of a judge and a mental health expert (psychiatrist), holds the hearing and determines the necessity for medical treatment and then the details of that treatment.
Fig. 4-5-3-2 shows the number of persons for whom public prosecutors applied for hearings and the number of persons conclusively disposed at hearings over the last five years. The number of persons for whom public prosecutors applied for hearings was 358 in 2010 and the number of persons involving a decision on a need for hospitalization or outpatient treatment 303.
Table 4-5-3-3 shows the number of persons for whom public prosecutors applied for hearings and the number of persons conclusively disposed at hearings by type of designated act in 2010.
At the hearings the court can request the director of a probation office to investigate the living conditions of the subject person. The probation office then investigates the living conditions of the subject person, including their residence and family status, current status of available social resources such as mental health and welfare services, etc., and reports the results to the court. The number of cases involving such investigation of the living conditions of the subject person was 372 in 2010 (Source: Annual Report of Statistics on Rehabilitation).